CVE-2026-8391
Other issue in the JavaScript Engine component
CVSS Score
5.3
EPSS Score
0.1%
EPSS Percentile
26th
Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | May 12, 2026 |
| Last Updated | May 19, 2026 |
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Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-45/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-47/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-48/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-51/
Credits
ggwhyp